Answer : 4. "WHO"
Explanation :

The World Health Organization (WHO) launched CoViNet, a global network of laboratories specializing in human, animal and environmental coronavirus surveillance. It aims to detect and monitor emerging coronaviruses, including potential new strains, to enhance risk assessment and inform WHO policies. CoViNet will expand surveillance capabilities to monitor MERS-CoV and other important coronaviruses, particularly in low- and middle-income countries, contributing to global public health preparedness.