Which of the following statements is true regarding scientific hypotheses?
a. there are no valuable hypotheses.
b. a testable hypothesis is valuable only if all evidence supports it.
c. every hypothesis is valuable, whether or not it is testable.
d. a testable hypothesis is valuable, even if evidence shows that it is false.

I would say D.  

A is incorrect by simple reasoning.

B is also incorrect. A hypothesis is made before evidence supports it, therefore, it doesn't matter if all evidence supports it,  as it shows an guess. It sometimes can also lead to more experimentation even if it's not true for the current experiment.

C is also incorrect. An untestable hypothesis isn't useful as you cannot test anything relating to it, and it cannot be proven or disproven.

Hope this helps!

b. accuracy of the data matters alot more than its number of digits, organization or amount of detail. quantitative observation is more accepted than the qualitative observation.