SQL Server :: How To Update Table Value From Another Table With Limit Rows

I have table a and would like update table a whose values from table b, but not update all rows at table a. Only update record ID in table a match record ID in tableC.

Here is my query

update a
set a.Desc = b.Desc,
a.Value = b.Value
from TableA a, TableB b
where a.name = b.name
and a.ID = b.ID
and a.ID in ( select ID from TableC)

I only have 12 a.ID match TableC, but above query update whole TableA.

How to only update 12 record at TableA from TableB?