Answer :
For the first question you have to use that tip that i've reminded you ;) answer variant C because ' that you are looking for ' it's the developed appositive which is isolated through that pair of commas ;)
For the second one the answer is variant D because it's no need of the usage of commas in the sentence. Variants A,B,C use the same rule for comma which is the wrong one.
For the second one the answer is variant D because it's no need of the usage of commas in the sentence. Variants A,B,C use the same rule for comma which is the wrong one.