A research conducted at the university of California

hello, any response to this question pls?

Sometimes, we gain knowledge not only from simply posting
OA's but also from exchanging ideas over what your opinions
are to a question....

I strongly go with first option..

Read the complete sentence with option 2,

A research conducted at the university of California reports that there is a direct
link between the price of a pack of cigarettes and how likely a teenager will be to start smoking.

Follow the parallelism rules--

Between X ... And Y-- X and Y must be parallel

here between is followed by a noun " the price" .. so "and" should be followed by noun form only.. i.e "likelihood" which is correctly written in case of option 1.

So option 2 is not parallel with the construction -- by use of "how likely".

Hope it helps.

As mentioned by Naveen, parallelism is maintained in A. A is correct here.

If B had to be used, the sentence should have been...
A research conducted at the university of California reports that there is an direct
link between how the pack of cigarettes will be priced and how likely a teenager will be to start smoking.

the AN in bold is an incorrect article in the sentence.
Could you please post the entire question for further analysis? Thanks!