Find a Formula for the N Th Term of the Arithmetic

Multiple Choice

Find a formula for the n th term of the arithmetic sequence. $a _ { 1 } = 11 , d = 4$

A) $\alpha _ { n } = 4 n + 11$
B) $a _ { n } = 4 n + 15$
C) $a _ { n } = 4 n + 7$
D) $a _ { n } = \frac { n } { 2 } ( 11 + 4 n )$
E) $a _ { n } = \frac { n } { 2 } ( 11 + 4 ( n - 1 ) )$