If 2 less than or equal too X less than or equal too 6, which of the following has the greatest value

From the list of choices that you have provided, √x + 2 is the greatest value.

I honestly don't see what 2 < x < 6 has to do with anything.

Well

2≤x≤6

so the values of x are: 2,3,4,5,6

and if we replace the values of the answers

if we replace x by 2 A√2=1.4; B √2+1=√3=1.7; C √2-1=√1=1; D√2-2=0

if we replace x by 3 A√3 = 1.7; B √3+1=√4 = 2; C √3-1=√2=1.4; D √3-2=√1=1

if we replace x by 4 A √4 = 2; B √4+1=√5=2.2 : C √4-1=√3=1.7; D√4-2=√2=1.4

if we replace x by 5 A √5 = 2.2; B √5+1=√6=2.44; C √5-1=√4 = 2; D√5-2=√3=1.7

if we replace x by 6 A √6 = 2.44; B √6+1=√7=2.65; C √6-1=√5 = 2.2; D√6-2=√4=2

you will notice that the group of answers B has the greatest values so the answer is : B