What is the primary effect of an increase in atomic number during beta decay?

In beta decay, a neutron transforms into a proton, which leads to an increase in the atomic number of the element. This transformation causes the element to change into another element on the periodic table because the identity of an element is determined by its atomic number, which is the number of protons in its nucleus. Therefore, as the atomic number increases due to the production of an additional proton, the element effectively changes into a new one, distinct from its original form.

This process is fundamental to the concept of transmutation in nuclear physics, where one element changes into another due to nuclear reactions. The increase in atomic number is key to reclassifying the element, confirming that the correct answer highlights this critical outcome of beta decay.