| Option | Meaning |
| Clear | Easily seen through; without obstruction or cloudiness. |
| Invisible | Unable to be seen; not visible to the eye. |
| Opaque | Not able to be seen through; not transparent. |
| Luminous | Emitting or reflecting light; glowing. |
Rearrange the following parts to form a meaningful and grammatically correct sentence:
P. a healthy diet and regular exercise
Q. are important habits
R. that help maintain good physical and mental health
S. especially in today's busy world