a. The average energy expenditure was bigger than 2,100 calories per day

b. The average energy expenditure was smaller than 2,100 calories per day

c. He could not reject the null hypothesis that the average energy expenditure was 2,100 calories per day

d. The average energy expenditure was either more than 2,100 calories per day or less than 2,100 calories per day

**c. He could not reject the null hypothesis that the average energy expenditure was 2,100 calories per day**

*p-value is higher than 0.05*