Heavy rainfall may cause

Which of the following statement(s) is correct?

I. Speed of light is $3\times {10}^8 \mathrm{m}/\mathrm{s}$

II. Speed of sound is $330 \mathrm{m}/\mathrm{s}$

III. Lightning is seen before thunder.

IV. Sound of thunder is heard before lightning.

Which of the following statement(s) is correct?

I.  Boiling and evaporation are simultaneous processes.

II.  Without boiling, evaporation cannot occur.

III.  Evaporation is independent of boiling.

IV.  Evaporation is more in windy day.

Which of the following statement(s) is correct?

I  Evaporation takes place at 100 °C.

II Evaporation takes place at all temperatures.

III Condensation occurs at all temperatures.

IV Condensation and evaporation occur at the same time.

Look at the water cycle below and answer the question that follows:

What change of state does X undergo to form clouds?