Many of today’s mathematicians use computers to test cases that
a. are either too time-consuming or involve too many variables to test manually, allowing the exploration of theoretical issues that were impossible to test a generation ago.
b. either take too much time or involve too many variables to be tested manually; allowing the mathematicians to explore.
c. would either take too much time or involve too many variables to test manually, allowing them to explore.
d. would either be too time-consuming or would involve too many variables to test manually; this capability allows the mathematicians to explore.
e. take too much time or variables to test manually; this capability allows the mathematicians to explore.

Many of today’s mathematicians use computers to test cases that are either too time-consuming or involve too many variables to test manually, allowing the exploration of theoretical issues that were impossible to test a generation ago.

Option A

Explanation:

One of the most useful inventions in scientific world are the computers. We can use different programming language and create programs in them. These programs help other to solve difficult problems. Most of the theoretical problems in science can be solved by using these programming features in computer within a specific time limit.

Otherwise, earlier mathematician used to take months to solve a complex mathematical problem manually, but now with the inclusion of computers, the mathematician can solve the problems containing more number of variables or other theoretical issues.