we are given
A coin is flipped until 3 heads in succession occur
so, firstly, we will find sample space
S={HHH , THHH , HTHHH, TTHHH , TTTHHH , HTTHHH , THTHHH , HHTHHHH, ......}
now, we are given that
list only those elements of the sample space that require 6 or less tosses
so, we can see that sample space
S={HHH , THHH , HTHHH, TTHHH , TTTHHH , HTTHHH , THTHHH , HHTHHHH, ......}
There are infinite such possibilities
so, there are infinite number of elements in space
and we know that
discrete sample space will always have finite elements
but we have infinite number of sample space elements here
so, this is not discrete sample space...........Answer