Sol and Gel are examples of examples of(a) Solid-solid colloids(b) Sol is a solid-liquid colloid and Gel is liquid solid colloid(c) Sol is a solid-solid colloid and Gel is a solid-liquid colloid

(d) Sol is a liquid-solid colloid and Gel is a solid-liquid colloid

The correct option is (b).
A sol is a type of colloid in which solid is the dispersed phase and liquid is the dispersion medium. Examples include milk of magnesia, mud etc.
A gel is also a category of colloid in liquid is the dispersed phase and solid is the dispersed medium. Examples include jelly, cheese etc.