Which of the following is NOT a requirement of testing a claim about two population means when 1 and 2 are unknown and not assumed to be​ equal? Choose the correct answer below. A. The two samples are dependent. B. Both samples are simple random samples. C. Either the two sample sizes are large ​(30 and ​30) or both samples come from populations having normal​ distributions, or both of these conditions are satisfied. D. The two samples are independent.