Complex sentence: Roy espoused the cause of the Narmada Bachao Andholan, a cause Guha supported too, but while he characterized her as courageous, he questioned her judgement and intellectual probity.
Split into simpler sentences: Roy espoused the cause of the Narmada Bachao Andolan, a cause Guha supported too. While he characterized her as courageous, he questioned her judgement and intellectual probity.