The clocks B and A will not be in sync when they cease to move in relation to one another because B already moved with speed hiigher than A and the time for B was slower. Also, since B expereinced transgressions from inertial to non-inertial frame of reference and vice versa, the clock B will lag after clock A.
The clock in C will tick slower than the clock in B after the force on B renders it stationary with respect to A because C continues moving at a high speed while B rests. However, at the moment when B just stopped, C and B will be still synchronized.
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