Instruction: Given the user's review, identify the user's sentiment from the listed options. Answer using one of the options.

Input:
Simply wonderful!  I'm very happy with these headphones.  In addition to sounding great, they are comfortable to wear for long periods.  I'm a long-time fan of Sennheiser, since listening to their "open air" headphones back around 1972.

<a data-hook="product-link-linked" class="a-link-normal" href="/Sennheiser-HD-600-Open-Back-Professional-Headphone/dp/B00004SY4H/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">Sennheiser HD 600 Open Back Professional Headphone</a>

Options:
A: very positive
B: positive
C: neutral
D: negative
E: very negative
Answer: A: very positive