The first one is correct. "It is like" the best decision you can ever make.
Saying it that way, is the same as saying that it would be the best decision that you can ever make, but adding more to it. Almost as if soeaking to someone who is overdramatic, and constantly say the word like.
I hope this helps
1. The adverb that modifies the verb is c) ever. Without it, it wouldn't be completely clear as to which time frame the speaker refers to. It may have been for example the last year, or in some other particular moment.
2. The adverb that modifies the verb is b) always. It adds to the sense of urgency of wearing a life jacket when rafting. Without it, the meaning of this sentence wouldn't be so precise.
I think it is possibly A or C if eliminating answers helps you.
The Vietnam war was broadcasted on live TV
And it is a downright mockery to talk to women of their enjoyment of the blessings of liberty while they are denied the use of the only means of securing them provided by this democratic-republican government - the ballot."