The answer would have to be será. The other answers would be incorrect because serás is plural, serán would be for taking about a specific person or thing and seremos would not be valid in this context.
Answer:
Usualmente me despierto a las ocho de la mañana
Explanation:
I was taught to repeat part of the question,
<em>example: What time do you usually wake up?</em>
<em> Usually I wake up at eight o'clock in the morning.</em>