1. The energy of one quantum (one photon) of electromagnetic radiation is given by

$E = h\nu = \frac{hc}{\lambda}$

where:

• $h$ = Planck's constant
• $\nu$ = frequency
• $\lambda$ = wavelength

So, higher frequency means higher energy, and equivalently, smaller wavelength means higher energy.

2. Now compare the given radiations:

• Radiowave (D): very low frequency, so lowest energy
• Yellow light (B): visible light, lower frequency than blue light
• Blue light (A): visible light, higher frequency than yellow light
• X-ray (C): very high frequency, so highest energy

Thus, the order of increasing energy is:

$D < B < A < C$

3. Match with the options:

• A: $C, A, B, D$ ❌ decreasing mostly
• B: $B, A, D, C$ ❌ radiowave should come first
• C: $D, B, A, C$ ✅
• D: $A, B, D, C$ ❌ blue has more energy than yellow, not less

Therefore, the correct option is:

$\boxed{\text{C: } D, B, A, C}$