Why do electromagnetic waves not require a medium for travel?
a) because electromagnetic waves travel too fast for stationary particles to move with them
b) because electromagnetic waves transmit energy without compressing the particles of the medium
c) because electromagnetic waves generate their own particles for compression and use these for movement
d) because electromagnetic waves move in two-dimensional space, the particles of mediums exist in 3-d space

B) because electromagnetic waves transmit energy without compressing the particles of the medium

Explanation:

Electromagnetic waves are the combination of electric and magnetic field which will oscillate perpendicular to each other. And the propagation of wave here is perpendicular to both electric and magnetic field.

So here in this type of wave propagation we do not require any medium as this is propagation of electric and magnetic field.

So here no need of compression or rarefaction of medium molecules and hence it do not need any medium to travel

so here correct answer is

B) because electromagnetic waves transmit energy without compressing the particles of the medium

the answer is d

lies a supermassive black hole called sagittarius a*, or sgr a* for short.