Within the for statement below, the variable irepresents $\_\_\_\_$ and the statement test: i $<=2$ represents a$($n$)\_\_\_\_.$

for i $($start: i $=1,$ test: i $<=2,$ increment $=1)$

a$.$ a loop counter; test condition

b$.$ the number of repetitions to perform; incrementation value

c$.$ a test condition; loop counter

d$.$ a starting value for the loop counter; loop counter