Steel Blocks a and B, Which Have Equal Masses, Are $\degree$

Steel blocks A and B, which have equal masses, are at TA = 300 $\degree$ C and TB = 400 $\degree$ C. Block C, with mC = 2mA, is at TC = 350 $\degree$ C. Blocks A and B are placed in contact, isolated, and allowed to come into equilibrium. Then they are placed in contact with block C. At that instant:

A) TA = TB < TC.
B) TA = TB = TC.
C) TA = TB > TC.
D) TA + TB = TC.
E) TA -TB = TC.