Will you help me plz plz plz What do all sponges have in common?

A: They can move.

B: They have a hard, outer shell.

C: They make their own food like plants do.

D: Their bodies are full of pores.

Many organizations release indexes used to measure the development of the world's countries. as we learned in this lesson, these indexes measure many factors, from life expectancy to happiness. in your opinion, what are the three most important factors we can use to determine how developed a country might be? explain your answers in a few sentences.