An individual running a marathon may experience periods of oxygen deprivation that can lead to A. anaerobic respiration in muscle cells, forming lactic acid

B. acrobic respiration in muscle cells, generating glycogen

C. anaerobic respiration in liver cells, producing glucose

D. aerobic respiration in liver cells, synthesizing alcohol

A. anaerobic respiration in muscle cells, forming lactic acid

Explanation:

Running marathon is a vigorous exercise, which often leads to excessive use of oxygen in the cells of the athlete. This causes the cells to switch from the aerobic (with oxygen) to the anaerobic (without oxygen) mode of respiration. This anaerobic respiration produces a product called LACTATE OR LACTIC ACID.

The lactic acid becomes excessive and gets stored in the muscle cells of the athlete. This often leads to cramps, muscle pulls etc. during the marathon. Therefore, an individual running a marathon may experience periods of oxygen deprivation that can lead to anaerobic respiration in muscle cells, forming lactic acid.

the diploid number of chromosomes is sometimes represented by the symbol 2n. for the fruit fly, the diploid number is 8, which can be written as 2n = 8, where n represents twice the number of chromosomes in a sperm or egg cell.

gold i'm pretty sure i might be wrong