Tengo is singular referring to "I or me"
Tienes is Singular referring to "you"
Tienen is Plural referring to "they" (not including you)
Yo siempre...is singular because there is only one subject...(you)
And it is referring to you (Yo)
This sentence in english is I always have a lot of Homework.
Therefore:
Your answer will be A. Tengo.