The given vectors are:

Two vectors are orthogonal if the dot product of the two vectors is zero, let's check:

As the product is not zero, then they are not orthogonal.
Now, we need to find the angle between them:

We already know u*v, now, let's find ||u|| and ||v||:

Now, replace these values, and solve for theta:

The answer is B. The vectors are not orthogonal. The angle between them is 91.3°