Consider the Turing machine M$2$ defined by this code:

def M$2($x$)$:

if len$($x$)<100$:

return True

while True:

pass

Which of the following sets is M$2$ a member of$?$ Check all that apply.

Group of answer choices

$1.($M$)$ is a regular set $\}$

$2.$ FIN $=\{$ M $|$ L$($M$)$ is finite $\}$

$3.$ INF $=\{$ M $|$ L$($M$)$ is infinite $\}$

$4.$ ~COF $=\{$ M $|$ ~ L$($M$)$ is infinite $\}$