Mass flow hypothesis of phloem transport

2023 Manipur 1 question

1. Identify the correct statements regarding Mass flow hypothesis. (A) Mass flow is faster than diffusion. (B) Mass flow is the result of pressure difference between the end points. (C) Different substances involved in mass flow move at different paces. (D) Mass flow can result through either a positive or a negative hydrostatic pressure gradient. Choose the correct answer from the options given below: