The angle between the asymptotes of the hyperbola x²/a² − y²/b² =1, the length of whose latus rectum is 4/3 , is ____________.
a) tan⁻¹(b/a)
b) tan⁻¹(a/b)
c) cot⁻¹(b/a)
d) cot⁻¹(a/b)