Refer to figures. 
When choosing a VFR level to fly, the semicircular rule should apply to enhance separation between VFR flights and reduce the risk of collisions. In simple words, aircraft following eastern magnetic tracks should be separated by 1000 ft with aircraft following western magnetic tracks. According to the semicircular rules:

• When an aircraft is following an eastern magnetic track between 0° and 179°, it should choose an altitude or flight level that will be odd plus 500 ft (3500 ft or FL35, 5500 ft or FL55, 7500 or FL75).
• When an aircraft is following an western magnetic track between 180° and 359°, it should choose an altitude or flight level that will be even plus 500 ft (4500 ft or FL45, 6500 ft or FL65, 8500 or FL85).

⇒ Since our Magnetic Track is 185°, the pilot should choose an altitude or flight level of even plus 500 ft (FL45 or 4500 ft).

ICAO Annex 2 
CHAPTER 4. VISUAL FLIGHT RULES

4.7 Except where otherwise indicated in air traffic control clearances or specified by the appropriate ATS authority, VFR flights in level cruising flight when operated above 900 m (3000 ft) from the ground or water, or a higher datum as specified by the appropriate ATS authority, shall be conducted at a cruising level appropriate to the track as specified in the tables of cruising levels in Appendix 3.