The correct option is D Surface area of imbibant
There are several factors that affect the process of imbibition.
1) Nature of imbibant- For example Toor dal adsorbs more water than wheat when kept in water. This is because proteins take up more water.
2) Temperature- Higher the temperature higher the rate of imbibition.
3) Surface area of imbibant- More the surface area, more is the ammount of imbibition.
Mass has no role to play in this process.