Q:

What is the inradius of a right-angled triangle?
A. The area of the triangle is known.
B. Any two sides of the triangle are known.
C. The perimeter of the triangle is known.

• 1
  B alone is sufficient
• 2
  A and C together are sufficient
• 3
  Any one statement is sufficient
• 4
  Either B alone or A and C together are sufficient
• 5
  All together are necessary