This question checks two things at once: whether you can spot a broken verb form, and whether you know the difference between "despite" and "instead of." Read the full sentence pair before picking a blank filler.
The correct choice is "scored; despite," since it keeps the verb tense consistent with the rest of the passage and uses the link word that means "although," not "in place of."
Let's summarize:
So the full, correct sentence reads: "The team scored more than 300 runs in 20 overs despite rains."