What are `d`-block elements? Why are they called transition metals?

What are d-block elements? Why are they called so?

Give four characteristics of f -block elements. Why are they called inner transition metals?

Why f-block elements are called inner transition metals?

Which block elements are called as transition metals ?

Which block elements are called transition elements ?

Why f-block elements are called inner transition elements ?

d-block elements are called ul("inner-transition elements.")

What are the characteristics of th transition elements and why are they called transition elements? Which of the d-block elements may not be regarded as the transition elements?