A reverse reaction is the chemical reaction moving both forward and backwards.
An example of this is Ammonium chloride ⇌ ammonia + hydrogen chloride
This is a symbol for reverse reaction ⇌
When the telomere becomes too short, the chromosome reaches a 'critical length' and can no longer be replicated.
If a scientist is planning to carry out such an experiment it wouldn't be appropriate to go and test this right ahead without any serious protection. It is always advised that scientists first collect data after they've created their initial hypotheses and read the required literature.
The answer is sunflower oil