Read the passage given below and answer the following question:
Indian neuroscientists will map the brains of people who either recovered from covid-19 or were asymptomatic to the disease to understand the reasons behind rising cases of depression, obsessive-compulsive disorder, anxiety and post-traumatic stress disorder among such patients. Scientists who claim that this is the first such study globally, have come up with a novel non-invasive neuro-imaging technique of magnetic resonance (MR) spectroscopy. The brain-mapping will start enrolling volunteers for the study by end-October. Scientists have noticed that SARS-CoV-2 is not just restricted to the respiratory system of the infected person.
Going beyond its common symptoms, it also causes neurological and neuropsychiatric disorders that affect the brain.
It is based on structural, spectroscopic, and behavioural studies to monitor the gradual changes in the brain non-invasively due to covid-19. The study may help in quantifying the impact of covid-19 on the mental health of survivors. Scientists have observed that apart from lung damage, covid-19 also causes neurological and neuropsychiatric disorders. A cohort study will be conducted for three groups—control, covid-19 asymptomatic patients, and covid-19 patients exhibiting mental health issues. The major rationale behind the proposed scheme is the increased level of oxidative stress in covid-19 survivors, which further contributes to the pathogenesis of several neurological diseases due to depletion of antioxidants. The impact of covid-19 on the brain continues to rise post-recovery. This further induces prolonged impact on the brain and may affect the brain with the progress of time.
In the following question, out of the give four alternatives, select the one which is similar in meaning of the given word.
COHORT