Differentiate between ‘must’ and ‘could’ in terms of their meaning and usage in making deductions.

A. The use of ‘must’ indicates a lower level of certainty in making deductions, while ‘could’ indicates a higher level of certainty or possibility.

B. Both ‘must’ and ‘could’ indicate the same level of certainty in making deductions.

C. The use of ‘must’ and ‘could’ is interchangeable in making deductions.

D. The use of ‘must’ indicates a higher level of certainty in making deductions, while ‘could’ indicates a lower level of certainty or possibility.