21, 25, 18, 29, 33, 18, … choose which pair of numbers comes next?

43, 18
41, 44
37, 18
37, 41 E. 38, 41

The answer is $\boxed{\text{D}}$.

In this sequence, each number is 4 more than the previous number, except for every third number, which is repeated. So the next number is 4 more than 33, which is 37. Then the sequence repeats with 18.

A. 43, 18 is incorrect because 43 is not 4 more than 33.
B. 41, 44 is incorrect because 44 is not 4 more than 41.
C. 37, 18 is correct because 37 is 4 more than 33 and 18 is

d="M549.7 124.1c-6.3-23.7-24.8-42.3-48.3-48.6C458.8 64 288 64 288 64S117.2 64 74.6 75.5c-23.5 6.3-42 24.9-48.3 48.6-11.4 42.9-11.4 132.3-11.4 132.3s0 89.4 11.4 132.3c6.3 23.7 24.8 41.5 48.3 47.8C117.2 448 288 448 288 448s170.8 0 213.4-11.5c23.5-6.3 42-24.2 48.3-47.8 11.4-42.9 11.4-132.3 11.4-132.3s0-89.4-11.4-132.3zm-317.5 213.5V175.2l142.7 81.2-142.7 81.2z"/> Subscribe on YouTube
repeated.
D. 37, 41 is incorrect because 41 is not 4 more than 37.
E. 38, 41 is incorrect because 38 is not 4 more than 33.