In order to prove that traingle adc is congruent to triangle abc by sas, we would need to show that
a) segment dc is congruent to segment bc
b) angle dca is congruent to angle bca
c) angle adc is congruent to angle abc
d) angle dac is congruent to angle bac

D) Angle DAC is congruent to Angle BAC

Step-by-step explanation:

Given:

The triangles ABC and ADC are congruent by SAS postulate.

SAS postulate means two corresponding sides are congruent to each other and the included pair of angles are also congruent to each other.

From the figure, consider the triangles ABC and ADC.

AB = AD  (Given)

AC = AC ( Reflexive property. Side AC is a common side to both triangles)

Now, the pair of angles included between these two pair of sides are angle BAC and angle DAC.

So, in order to prove the two triangles congruent by SAS postulate, we need to prove angle DAC congruent to angle BAC. Therefore, the correct option is option D.