DNA contain genetic information of the organism that define traits of the organism and subsequently traits of the Population.
Genetic engineering changes the Sequence of DNA and thus cause the variety in traits. Deletion bases would also lead to alteration in DNA and exchange of segments between chromosomes is known as crossover which is essential for variety of traits.
Accurate replication would produce the same traits in a population so it is least likely to add variety of traits.
Your answers are going to be: Will succeed, Will reevaluate, and Will create.
Reason: Had is past tense and Has is present tense. Will is the only word that indicates that the actions <em>will be done</em> in the future instead of having already <em>been done.</em>