Answer:
The correct answer will be options:
1. option-B
2. option-B
Step-by-step explanation:
Case I
Making an act of direct observation is a way of collecting information in which the observer observes a natural behavior in its natural environment without making assumptions.
In the given questions, the case of direct observation will be when the height of the plant is measured on 23rd day. Thus, Option-B is the correct answer.
Case II
In the given question, the researcher wants to determine the effect of fertilizer on the growth of the plant so he decides to perform an experiment by giving fertilizers to plants.
This is an act of performing an experiment and thus Option-B is the correct answer.