The correct option is
C m∠B=m∠QGiven: △ABC≅△PQR
Note––––––: Congruent triangles are named by listing their vertices in corresponding orders.
∙A corresponds to
P
∙B corresponds to
Q
∙C corresponds to
R.
∵ The triangles are congruent.
∴ The corresponding angles must be equal in measure.
∙ m∠A=m∠P
∙ m∠B=m∠Q
∙ m∠C=m∠R
Hence, options(a.), (b.) and (c.) are correct.