I think silver maples are a scapegoat for the generations of incompetent that planted them in the wrong spot and didn't prune them properly. If pruned properly and planted in the right spot, ie open grassy areas, they are attractive trees. I have a newfound respect for them after these last two droughty summers and they still look solid. Also I rarely see them falling apart or volunteers popping up around here. I'm not saying they are a top tree that should be planted more its just that they have some things going for it if used properly. Longtee, I'd be inclined to remove it however its tough to imagine what it would look like it if I removed B (or A) from this view point. If I belive the canopy would fill in (depending on the laterals of the remaining trunk) I'd try it. I did it on a tree slightly smaller than yours, maybe 15' tall. Looked funny for a couple years but looked normal thereafter. I'd then remove C the following year.

Looks like a tiny thing, Will probably develop a replacement on its own. Rather than thinking about snipping at it, maybe work on why the original leader died.

I don't know why it should be considered a mistake......although not as common a single trunked specimens, Freeman maples are available as multi-trunked selections as well. Typically these are listed in grower catalogs as "clump" maples. A number of maple species are inclined to grow with multiple trunks, sugar maples (one of the Freeman's parent species) among them. Because they are less common than single trunked trees and generally held for a longer period to confirm the viability of all the trunks before they are marketed, multi-trunked trees typically carry a higher price tag. "Should be grown as a single leader" is an artificial concept the public has assigned to various trees. As stated previously, as maples mature, single leaders - if they exist at all - disappear, leaving the tree without a dominant growing point but a broad, balanced canopy. There is no viable reason why they "must" be grown with a defined single leader. If the trunks are well spaced and approximately equal in proportion to each other and context, then you should have no problems. Prune as you would with the more common single trunked forms, removing conflicting branching and watching for narrow crotch angles. IMO, multi-trunked or clumped trees offer a much more interesting presentation, as well as a nearly immediate sense of more maturity, than do the more common single trunked selections.

From what I can see, I wouldn't, but of course you have to live with the tree. I don't see any aesthetic drawbacks to doing what I suggested because the two branches we're talking about will emerge so close to the main leader that they will 'read' as originating from the main leader. I have several maples in the landscape and a couple of dozen in containers. I prune healthy trees any time I feel like it - usually with a purpose/plan, but with no regard to 'bleeding'. I recommend late dormancy pruning for two reasons. Branches that need pruning and o/a form are much more visible - the future growth habit of the tree more readily discernible, and the chance of disease spread is reduced greatly. The healing of any pruning wounds is more rapid in spring/early summer than at any other period in the growth cycle, so for me, that clinches the case for late winter/early spring pruning. I've never seen a case documented where 'bleeding' affected the long or short term vitality of an Acer, much less a documented case of a tree 'bleeding to death'. I often suggest that if the sap flow is a concern - wait until the tree appears to be resting after the spring growth flush has matured. There should be very little bleeding then. You can also make a case for late dormant pruning from an energy management perspective. What sense does it make to prune the growth off immediately after the tree has spent nearly all its energy reserves to build it. If you prune BEFORE budswell, the tree will move energy from the roots into the remaining organs and not the parts you intend to remove. Al