Q. The cable for a pre-stressed concrete simply supported beam subjected to uniformly distributed load over the entire span should ideally be ?

• (A) placed at the centre of cross-section over the entire span
• (B) placed at some eccentricity over the entire span
• (C) varying linearly from the centre of cross-section at the ends to maximum eccentricity at the middle section
• (D) parabolic with zero eccentricity at the ends and maximum eccentricity at the centre of the span