The phrase "becomes obvious why" is grammatically correct and can be used in written English.
It is typically used to indicate that something has become clear or understandable. Example: After studying the data, it becomes obvious why the company's profits have been decreasing.
When seen in this light, it becomes obvious why focusing on mental health is a dodge.
At the end of the book, in a twist that I won't give away, it becomes obvious why this story is told from Serena's point of view.
But as Mr Celik outlines the possible applications for reversible data-hiding, it becomes obvious why preserving image integrity is so critical.
As soon as we land, it becomes obvious why people are prepared to put themselves through aerial bucking bronco hell to reach Mal País.
Surveying the assembled crew, with their standard-issue gangster coats and tattoos, it becomes obvious why Kaliningrad has a reputation as a smugglers' haven.It used to be Königsberg, city of Kant and celebrated Prussian architecture.
And as one watches the plot thicken by the day, it becomes obvious why suspicion is the staple diet of Italian hearts: there's simply so much about which one can be suspicious.
It also became obvious why the apartment, 725 square feet and with a view of the Empire State Building from the kitchen, had not sold.
It soon became obvious why Media Laboratory faculty were among the world's most frequent fliers.
I don't ever remember seeing the Observer but, after returning home in January, 1957,, it became obvious why.
Yes, he left that first putt miles short, but it soon became obvious why he was performing an absurd balancing act there, with Todd sending his putt skidding hysterically off the green.
Without sight and with only minimal sound, it soon became obvious why the world through which a deaf-blind person navigates is practically incomprehensible to anyone who can hear and see.
