Which solution would most likely cause a plant placed in it to become firmer and more rigid?

Hypotonic solution.

Explanation:

Hypotonic solution is defined as a solution which has lower solute concentration with comparison to another solution of a cell.

The plant cell is takes up water from the outside of the cell where high water concentration is present so water is moves in of the cell with the help of osmosis process and start to become swell, but with the help cell wall which is present on cell prevents it from bursting when the plant cell is present in this solution (hypotonic solution).

So, if the plant cell is placed in a hypotonic solution it to become firmer and more rigid.

2%? i tried finding the exact sorry if it's not 100% correct ; -;

answer;

-vessels in the chest

the diagnosis of angina pectoris literally means "vessels in the chest"

explanation;

-angina pectoris is the medical term for chest pain or discomfort due to coronary heart disease.it is the chest pain due to an inadequate supply of oxygen to the heart muscle. the pain is typically severe and crushing, and it is characterized by a feeling of pressure and suffocation just behind the breastbone.

agina pectoris is caused by reduced blood flow to your heart muscle. the blood carries oxygen, which the heart muscle needs to survive. when the heart muscle isn't getting enough oxygen, it causes a condition called ischemia