Which of the Following Vectors Are Orthogonal?
A) $\langle 1,2\rangle \text { and }\langle 2,4\rangle$

Multiple Choice

Which of the following vectors are orthogonal?

A) $\langle 1,2\rangle \text { and }\langle 2,4\rangle$
B) $\langle 1,2\rangle \text { and }\langle-1,-2\rangle$
C) $\langle-1,-2\rangle \text { and }\langle 1,-1\rangle$
D) $\langle-1,-2\rangle \text { and }\langle-2,1\rangle$