Right answer:
b. el almuerzo
Here papel can be translated as napkin. In fact, this sentence would be better if you use the word servilleta that is a square piece of cloth or paper used at a meal to wipe the fingers or lips. On the other hand, necesito is the conjugation of the verb necesitar for the first person singular in the simple present. Finally:
Necesito papel para el almuerzo
It's also valid:
Necesito servilleta para el almuerzo
Necesito servilletas para el almuerzo
