Which one of the following is a requirement for a good primer? select one: a. guanine and cytosine should make up less than half of the total base pairs b. melting temperatures of primer should be between 55-80 degree celsius c. primers should be short (under 15 base pairs) d. primers should end in the 5' end e. contains many long runs with four or more of the same base in a row

B. Melting temperatures of primer should be between 55-80 degree Celsius.

Explanation:

Bacause the melting temperature controls the binding of the primers to your template DNA. At melting temperature 50% of the primer molecules are bound to their corresponding target sequence. If the difference in melting temperature between the two primers is too high, it might be difficult to find experimental conditions where both primers can bind to their target.