Response: Option D.
Justification:
Active transport refers to how molecules or solutes travel through a membrane based on solute concentration differences.
This process is constant due to diffusion, which ensures ongoing movement of solutes across the membrane. Cells have reduced sodium (Na+) levels but increased potassium (K+) levels. Therefore, sodium's electrical and concentration gradients promote the ion's entry into the cell, assisted by the positive charge of Na+, which encourages inward movement to the negatively charged interior.
Thus, the right choice is D.
1) Magnification increases through powers like 10x, 100x, 1000x, and even up to 10,000x.
2) Begin focusing with the lowest magnification lens, usually 10x; once in focus, switch to medium power (100x) and fine-tune using the fine adjustment knob. Avoid using the coarse focus on medium or high powers. Then move to the highest power (typically 1000x), and carefully focus again with the fine knob.
3) To keep the lens clean and prevent dust or fog buildup, proper handling and storage are necessary.