
A.
4√6 cm 
B.
3√6 cm 
C.
6√6 cm 
D.
2√6 cm
Correct Answer: Option A
Explanation
From Pythagoras theorem
OA^{2} = AN^{2} + ON^{2}
7^{2} = AN^{2} + (5)^{2}
49 = AN^{2} + 25
AN^{2} = 49 – 25 = 24
AN = (sqrt {24})
= (sqrt {4 times 6})
= 2√6 cm
AN = NB (A line drawn from the centre of a circle to a chord, divides the chord into two equal parts)
AN + NB = AB
2√6 + 2√6 = AB
AB = 4√6 cm