To determine which student is correct, let's analyze the relationship between wavelength and frequency.
According to the wave equation:
\[ c = \lambda \cdot f \]
where:
- \( c \) is the speed of light (a constant),
- \( \lambda \) is the wavelength,
- \( f \) is the frequency.
From this relationship, we can see that wavelength and frequency are inversely related:
- If the wavelength increases, the frequency must decrease to keep the speed of light constant.
- If the wavelength decreases, the frequency must increase.
- If the wavelength remains the same, the frequency remains the same.
Now, let's assess each student's claim:
- Darius: Wavelength increases, frequency increases. (Incorrect)
- Kathryn: Wavelength increases, frequency remains the same. (Incorrect)
- Anya: Wavelength decreases, frequency increases. (Correct)
- Franco: Wavelength remains the same, frequency decreases. (Incorrect)
The only correct statement is from Anya. Therefore, Anya is the correct student.