Write the First Five Terms of the Arithmetic Sequence $a_{1}=21, d=7$

Multiple Choice

Write the first five terms of the arithmetic sequence.
- $a_{1}=21, d=7$

A) $21,28,35,42,49$
B) $21,7,56,84,112$
C) $21,7,35,42,49$
D) $7,28,49,70,91$