Question

Which of the following gives the best way to combine these two sentences?

The problem has certainly gained a good deal of traction in public
debates. The fact that it has gained such traction makes us wonder
why isn't there more significant action to combat the gender pay gap.

Answer 1

The first option.

Step-by-step explanation:

The second and third option are wrong because you do not need the colon to combine these sentences. The last one is wrong because those are not complete sentences, they are fragments.