Which of the following laws amends RA 5527?

The correct choice is indeed RA 6138, as it specifically amends Republic Act 5527, which is known as the "Philippine Medical Technology Act of 1969." RA 6138 was enacted to modify and enhance certain provisions in RA 5527, reflecting changes in the practice and regulation of medical technology in the Philippines.

This amendment was necessary to address the evolving landscape of medical technology, including updates to the education and qualification requirements for medical technologists and the establishment of more rigorous standards for practice. By amending the original act, RA 6138 aimed to ensure that the profession remains relevant and capable of meeting the needs of modern healthcare.

In contrast, the other options—RA 1234, PD 2034, and RA 7485—do not specifically deal with amendments to RA 5527, thus making them incorrect in relation to the question about the amendment of the Philippine Medical Technology Act. These other laws pertain to different areas of legislation and do not impact the regulatory framework established by RA 5527.