Two identical light nuclei, each having mass number \(A/2\) and binding energy per nucleon \(B_1\), undergo a fusion reaction to form a single stable nucleus with mass number \(A\) and binding energy per nucleon \(B_2\), where \(B_2 > B_1\). Let \(m_Y\) represent the rest mass of one initial nucleus, \(m_X\) represent the rest mass of the fused nucleus, and \(c\) represent the speed of light in a vacuum. Which of the following correctly compares \(m_X\) to \(2m_Y\) and provides the correct physical justification?