173.

Match the correct sorting technique:

It starts by comparing every two elements (i.e. 1 with 2, then 3 with 4...) and swapping them if the first should come after the second. It then places each of the resulting lists of two into lists of four, then combines those lists of four, and so on; until at last two lists are combind into the final sorted list.

Merge sort takes advantage of the ease of merging already sorted lists into a new sorted list. Merge sort scales well to very large lists