Final answer:
The concept of ahimsa (non-violence) is the true commonality across Hinduism, Jainism, and Buddhism, while other options provided do not equally apply to all three religions.
Step-by-step explanation:
Of the options provided regarding Hinduism, Jainism, and Buddhism, the only one that holds true equally for all three is C) Acceptance of the concept of ahimsa (non-violence). Ahimsa is a core principle in all three religions, emphasizing compassion and non-violence towards all living beings. Rejection of the authority of the Vedas would not be a commonality, as Jainism and Buddhism do not derive their teachings from the Vedas, which are central to Hinduism. Conversely, both Buddhism and Jainism arose as reforms that challenge the traditional supremacy of the Vedas and the Brahminical system. The belief in karma and the cycle of samsara (reincarnation) are also fundamental concepts in these religions, which advocate for moral living as a way to achieve liberation from this cycle. However, Jainism and Buddhism interpret and practice these concepts in distinct ways that differ from the traditional Hindu perspective.