निम्नलिखित में से किस सिख गुरु को पवित्र ग्रंथ 'आदि ग्रंथ' का संकलनकर्ता माना जाता है?

Who among the following Sikh Gurus founded the town and community at Kiratpur Sahib?

Which Sikh Guru is credited with standardizing the script of Punjab into the Gurmukhi script?

In which year was Guru Nanak Dev Ji's 550th birth anniversary (Parkash Purab) celebrated?