In a living organism, what is an organ? A. a group of similar cells that perform a common function
B. a structure composed of a number of tissues that work together to perform a specific task
C. the shell or skin of an organism
D. functional unit, or building block, of all organisms; smallest unit that can carry on the activities of life

An organ is a group of tissues in a living organism that has a specific form and function. Organs are grouped together into organ systems. Organ systems perform a specific task.

Explanation:

B

Explanation: An organ is a differentiated part of the human body, formed by different tissues, that maintains its structure, vascularisation, and capacity to develop physiological functions with a significant level of autonomy.

answer: 45

explanationyou have to add as well to be it could be