Explanation

Linkage in plants was first demonstrated by Bateson and Punnett using sweet peas (Pisum sativum), but the term 'linkage' and chromosomal basis were later confirmed by Morgan in Zea mays (maize). However, historically, the first observation of linkage is attributed to Bateson and Punnett with sweet peas. Wait, let me double-check. Bateson and Punnett worked on sweet peas (Lathyrus odoratus) and observed linkage. The question asks for the 'first attempt'. Lathyrus odoratus is sweet pea. Zea mays was used by Morgan later. So A is likely correct. Let me verify. Bateson, Saunders, and Punnett (1905) reported linkage in Lathyrus odoratus. So A is correct. The option says 'Lathers odorous' which is a typo for Lathyrus odoratus. I will stick with A.