The atomic radius of hydrogen atom is

The atomic radius of a hydrogen atom is typically defined by the Bohr radius, which represents the radius of the electron's orbit in its ground state (n=1). According to the Bohr model, this value is approximately 0.529 Å or 52.9 picometers [1]. However, in many standard educational contexts and specific experimental measurements of the covalent radius, the value for the hydrogen atom is frequently cited as 37 picometers [1]. While the Bohr radius (53 pm) is a physical constant representing the most probable distance of the electron from the nucleus, the value of 37 pm is the standard covalent radius used to describe the hydrogen atom's size when bonded in a molecule like H2. Given the options provided, 37 picometer is the intended answer commonly found in chemistry textbooks for the atomic radius of hydrogen.

Sources

1. [1] https://en.wikipedia.org/wiki/Atomic_radii_of_the_elements_(data_page)