In the following question, out of the four alternatives, choose the word which best expresses the meaning of the given word and click the button corresponding to it.
Pollen is a male plant gamete. When microspores produced after meiosis process on microsporangia of male gametophyte undergo mitosis and forms pollen grains.
The weights of 4 boxes are 20, 30, 40 and 60 kilograms. Which of the following cannot be the total weight, in kilograms, of any combination of these boxes and in a combination a box can be used only once?