The phrase "a challenge for which" is correct and usable in written English.
It can be used when referring to a specific challenge that requires a certain action or response.
Example: "This is a challenge for which we must prepare thoroughly to ensure success."
Alternatives: "a challenge that requires" or "a challenge needing".
He should relish it – for this is a challenge for which he is unusually well suited.
Tapit will face a challenge for which he may not be ready, and asking too much of a horse can create debilitating problems, mentally and physically.
As a student, Kirn found having to read "whole books, many of them old, obscure and difficult," a challenge for which he was ill prepared.
Although he has been the object of journalistic fascination for some time now, he's about to face a whole new kind of scrutiny, and stumping coast to coast in the heat of a bitterly contested presidential campaign is a challenge for which no prior experience can fully prepare a person.
Managing data exchange in scientific workflow simulations is a challenge for which existing solutions have only limited success.
"The challenge of drug trafficking is a shared challenge, and it's a challenge for which Mexico has made great efforts," said Jose Antonio Meade, Mexico's foreign affairs minister, in statements on Monday.
What is sometimes called "sentiment" or "tone" analysis presents a challenge for computers, which can stumble over simple words.
But those low interest rates also present a challenge for JPMorgan, which is dealing with glut of deposits.
Expansion has been a challenge for Polaroid, which invented the instant photography business, as sales of digital cameras have eroded its core.
That has created a challenge for Participant, which is usually eager to have its films become talking points in a national debate.
Reining in China's most gung-ho province has long been a challenge for Beijing, which is on guard against centrifugal forces in the coastal region.
