Identify the correct statements from the following.

The relative luminosity of the human eye is maximum at a wavelength of $555 \text{ nm}$.

Luminous efficiency is the ratio of total luminous flux to the total radiant power. For a monochromatic source of wavelength $555 \text{ nm}$, the luminous efficiency is maximum. A white light source contains various wavelengths across the visible spectrum, for most of which the relative luminosity is less than $1$. Thus, the overall luminous efficiency of a white light source is less than that of a monochromatic source at $555 \text{ nm}$.

Illuminating power is proportional to the luminous flux. Since the luminous efficiency of the $555 \text{ nm}$ source is higher, its luminous flux and illuminating power will also be greater than those of a white light source of the same radiant power.

A monochromatic source at a different wavelength (e.g., $700 \text{ nm}$) has a very low luminous efficiency, which can be lower than that of a white light source. Thus, statements (3) and (4) are incorrect.