Find the Dot Product Of $\mathbf { u }$ And $\mathbf { v }$

Multiple Choice

Find the dot product of $\mathbf { u }$ and $\mathbf { v }$ .
$$\mathbf { u } = \langle 1 , - 6 , - 4 \rangle , \mathbf { v } = \langle 6,4,9 \rangle$$

A) $- 54$
B) 10
C) $\langle 6 , - 24 , - 36 \rangle$
D) 18
E) $\langle 7 , - 2,5 \rangle$